[Richard Wallace]

Originally Posted by Al Skierkiewicz

... the end plate of the Chalupa motor(s) is not a mounting bracket, it is an integral part of the motor, unlike the van door and window motors which have obvious mounting brackets. Those motors have unusual mounting flanges with an odd position for mounting holes. It had been ruled in the past that those mounting brackets could be modified. In the case of the Chalupa in particular, the magnetic structure may be compromised by changes in the motor frame.

A red flag for me comes in response to the end of R36 should the intended modification lighten the motor or cause a problem with structural integrity.

As always, it is best to use the Q&A for official answers. I do not speak for FIRST.

Al,
The 2005 FRC Robot Inspection Checklist Manual v. 1.2 contains some unclear guidance on p. 77 under the heading Motor Modifications, saying in one place that it is OK to modify housings and in another place that it is not OK to modify integral mechanical parts. I agree with your interpretation that in the case of the big CIM motor the endplates are integral mechanical parts, not merely elements of a housing. While machining the endplates would not compromise the magnetic structure (since the endplate material is not ferromagnetic), such machining could potentially cause a problem with structural integrity and therefore violate one of the main intents of <R36>.

I also agree with your overall conclusion that neither this thread nor any other discussion on CD can be considered authoritative; only FIRST Q & A can provide an official resolution to a question of rules interpretation. I hope that someone with an interest in this topic will submit a question there so that we get clarification of what modifications are and are not allowed for mounting the big CIM.

And let me repeat, the preferred method should be to use the AndyMark (or some other) adapter kit. This will facilitate easy replacement of a motor at an event if necessary.